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TrojanSpy.Win32.Muyem.A

April 12, 2019
 Analysis by: Janus Agcaoili
 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan Spy

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

This Trojan Spy arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It steals system information.

  TECHNICAL DETAILS

File Size:

784,896 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

11 Apr 2019

Arrival Details

This Trojan Spy arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan Spy adds the following folders:

  • %ProgramData%\{Random String}
  • %ProgramData%\{Random String}\files
  • %ProgramData%\{Random String}\files\Autofill
  • %ProgramData%\{Random String}\files\CC
  • %ProgramData%\{Random String}\files\Cookies
  • %ProgramData%\{Random String}\files\Downloads
  • %ProgramData%\{Random String}\files\Files
  • %ProgramData%\{Random String}\files\History
  • %ProgramData%\{Random String}\files\Soft
  • %ProgramData%\{Random String}\files\Soft\Authy
  • %ProgramData%\{Random String}\files\Wallets
  • %ProgramData%\{Random String}\files\Wallets\ElectronCash
  • %ProgramData%\{Random String}\files\Wallets\Electrum
  • %ProgramData%\{Random String}\files\Wallets\ElectrumLTC
  • %ProgramData%\{Random String}\files\Wallets\Ethereum
  • %ProgramData%\{Random String}\files\Wallets\Exodus
  • %ProgramData%\{Random String}\files\Wallets\JAXX
  • %ProgramData%\{Random String}\files\Wallets\MultiDoge

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData in Windows Vista, 7, and 8.)

Dropping Routine

This Trojan Spy drops the following files wherein it saves the information it gathers:

  • %ProgramData%\{Random String}\c
  • %ProgramData%\{Random String}\history
  • %ProgramData%\{Random String}\ld
  • %ProgramData%\{Random String}\historych
  • %ProgramData%\{Random String}\wd
  • %ProgramData%\{Random String}\files\cookie_list.txt
  • %ProgramData%\{Random String}\files\outlook.txt
  • %ProgramData%\{Random String}\files\information.txt
  • %ProgramData%\{Random String}\files\screenshot.jpg
  • %ProgramData%\{Random String}\files\Autofill\Google Chrome_Default.txt
  • %ProgramData%\{Random String}\files\CC\Google Chrome_Default.txt
  • %ProgramData%\{Random String}\files\Cookies\Google Chrome_Default.txt
  • %ProgramData%\{Random String}\files\Cookies\cookies_Mozilla Firefox_dxxbjsgn.default.txt
  • %ProgramData%\{Random String}\files\Cookies\Edge_Cookies.txt
  • %ProgramData%\{Random String}\files\Cookies\IE_Cookies.txt
  • %ProgramData%\{Random String}\files\Downloads\Google Chrome_Default.txt
  • %ProgramData%\{Random String}\files\Files\Default.zip
  • %ProgramData%\{Random String}\files\History\Google Chrome_Default.txt
  • %ProgramData%\{Random String}\files\History\history_Mozilla Firefox_dxxbjsgn.default.txt

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData in Windows Vista, 7, and 8.)

Download Routine

This Trojan Spy accesses the following websites to download files:

  • http://{BLOCKED}est.com/380
  • http://{BLOCKED}est.com/freebl3.dll
  • http://{BLOCKED}est.com/mozglue.dll
  • http://{BLOCKED}est.com/msvcp140.dll
  • http://{BLOCKED}est.com/nss3.dll
  • http://{BLOCKED}est.com/softokn3.dll
  • http://{BLOCKED}est.com/vcruntime140.dll

It saves the files it downloads using the following names:

  • %ProgramData%\freebl3.dll
  • %ProgramData%\mozglue.dll
  • %ProgramData%\msvcp140.dll
  • %ProgramData%\nss3.dll
  • %ProgramData%\softokn3.dll
  • %ProgramData%\vcruntime140.dll

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData in Windows Vista, 7, and 8.)

Information Theft

This Trojan Spy steals system information.

It gathers the following data:

  • User credentials from the following:
    • Telegram Desktop
    • Mozilla Thunderbird
    • Filezilla
  • Screenshot of the desktop during execution
  • Browser Information
    • Autofill Data
    • Cookies
    • Browsing History
    • Download History
    • Browser Credentials
  • System Information
    • ISP
    • Coordinates
    • ZIP
    • City
    • Country
    • IP
    • Video Card
    • RAM
    • CPU Count
    • Processsor
    • Time Zone
    • Local Time
    • Keyboard Language
    • Display Language
    • Display Resolution
    • User Name
    • Computer Name
    • Windows OS
    • Working Directory
    • GUID
    • Machine ID
    • Date
    • Version

Stolen Information

The stolen information is saved in the following file:

  • %ProgramData%\{Random String}\files\US_{GUID}{Date}.zip

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData in Windows Vista, 7, and 8.)

It sends the gathered information via HTTP POST to the following URL:

  • http://{BLOCKED}est.com

Other Details

This Trojan Spy connects to the following URL(s) to get the affected system's IP address:

  • http://ip-api.com/line/

It does the following:

  • Does not proceed with its routine when the default user locale name are any of the following:
    • Russian
    • Belarussian
    • Uzbek
    • Kazakhstan
    • Azerbaijani
  • It targets the following browsers:
    • Chedot
    • Mustang
    • Suhba
    • TorBro
    • Elements
    • Cent
    • QIP
    • URAN
    • CocCoc
    • Vivaldi
    • Epic Privacy
    • Sputnik
    • Maxthon5
    • Nichrome
    • Comodo Dragon
    • Opera
    • Orbitum
    • Torch
    • Amigo
    • Kometa
    • Chromium
    • Google Chrome
    • K-Meleon
    • IcaCat
    • BlackHawk
    • Cyberfox
    • Waterfox
    • Pale Moon
    • Mozilla Firefox
  • It may also possess the capability to steal information from various cryptocurrency wallets:
    • *btc*.dat
    • *wallet*.dat
  • Targets the following cryptocurrencies:
    • JAXX
    • MultiDoge
    • ElectronCash
    • Electrum
    • Electrum-LTC
    • Ethereum
    • Exodus
  • Will try to delete itself, the information gathered, and its network activity to destroy any evidence of its execution

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

14.932.08

FIRST VSAPI PATTERN DATE:

11 Apr 2019

VSAPI OPR PATTERN File:

14.933.00

VSAPI OPR PATTERN Date:

12 Apr 2019

Step 1

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 2

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %ProgramData%\{Random String}

Step 4

Scan your computer with your Trend Micro product to delete files detected as TrojanSpy.Win32.Muyem.A. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check the following Trend Micro Support pages for more information:


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